Example #1
0
        public EvaluatorResult Evaluate(IInterpreterContext context, string expression)
        {
            string LeftValue;

            try
            {
                if (checkForExistence)
                {
                    var res = context.PropertyExists(leftSide);

                    // just check existence, nothing else, or it does not exist
                    if (res == false || NoRightSide)
                    {
                        if (IsNegate)
                        {
                            res = !res;
                        }
                        return(new EvaluatorResult(res, string.Empty));
                    }
                }
                // existence of property is assumed (it is either checked or no "?" was present
                if (evaluator is Evaluator.ExpressionEvaluator)
                {
                    LeftValue = context.EvaluateProperty(leftSide);
                }
                else
                {
                    var evalRes = evaluator.Evaluate(context, leftSide);
                    if (evalRes.Result == EvaluationResultValues.True)
                    {
                        LeftValue = evalRes.Value;
                    }
                    else
                    {
                        LeftValue = "error";
                    }
                }
            }
            catch (Exception ex)
            {
                return(new EvaluatorResult(ex));
            }

            LeftValue = LeftValue.ToLower();

            bool retVal;

            if (CompareEqual)
            {
                retVal = LeftValue == rightSide;
            }
            else
            {
                retVal = LeftValue != rightSide;
            }
            // leading "!" is valid for the complete if-clause
            if (IsNegate)
            {
                retVal = !retVal;
            }
            return(new EvaluatorResult(retVal, string.Empty));
        }